Liquid dispenser



Oct. 30, 1934. w. J. PETER LIQUID DISPENSER Filed Jun 5. 1933 3Sheets-Sheet 1 d (n s n I m 53.: a-

e INVENTOR w/LL/HM J. PETER @M+W n.fn-romunm lll FIG. 2

Oct. 30, 1934. w. J. PETER 1,978,597

LIQUID DISPENSER Filed-June 5 1953 s sheets-sheet 2 INVENTOR WILL/HM JPE'E/ Iy y di I n ..1 C.-.

Oct. 30, 1934. w. J. PETER LIQUID DISPENSER 3 Sheng-sheet 3 Filed June5, 1935V g lNvl-:N'roR wIlL/HM J. PEN-'1? I BY @Ale/Irv P W ATTORNEYSPatented Oct. 30, 1934 LIQUID DISPENSER William J. Peter, New

York, N. Y., assigner to Aqua Systems Incorporated, New York, N. Y., a

corporation of New York Bpiirggioarnne 5, wasrserialNofsmase" tained inthe apparatus during intervals of nonuse, as when not dispensing.Although referring generally to gasoline as the liquid being hantiled ordispensed, it is understood that this term is used generically to meanany liquid.

A primary purpose of my invention is to produce meter dispensingapparatus, pumps and the like, the conduit flow system of which ismaintained full of gasoline, from the discharge hose nozzle back to thesource of supply; and this confined gasoline is kept at substantially aconstant and more particularly a normal hydrostatic may expand` theconiinedoliquid and-produce ex? pressure or head by the normalizingmeans here- 'in described, when the apparatus is not dispensing.- Duringintervals when not in dispensing use, the hydrostatic pressure in the-flow lines may vary over a wide range. For example, the pressure maydecrease by reason-of contraction er shrinkage of the confined liquidcolumn in cessive or abnormal pressure resulting in leakage and firehazard. My invention compensates for and equalizes both conditions byautomatically forcing gasoline into the ow lines, particularly theoutlet discharge line, should there be a tendency for the pressure todecrease; and conversely, drawing oi or absorbingsome of. the liquidpressure shouldite-increase.VA

, By reason Yof the foregoing, the entire conduit flow system ismaintained positively lled with a solid column of confined liquid atsubstantially a constant or a satisfactory normal pressure with theresult that a dispensing operation is positive from its beginningbecause the ow is a continuous one, free from air and vapor. Achievingthese ends by my invention prevents air from entering the flow lines andperfects the operation of a visible flow indicator, one general typeknown as the visi gage, by keeping its liquid level in the glasscontainer at maximum height. This invention, therefore, insures a fullflow and a true indication thereof from the inception of the dispensingoperation, by avoiding air pockets in the line with initial bubbling orblowing of gaseous vapor and inaccurately measured liquid ow as aconsequence thereof.

In addition to the foregoing, a special object is to produce safegasoline meter dispensing apparatus. This phase of the inventioncomprises means for relieving the excess internal pressure from thegasoline confined in the iiow lines when the apparatus is not in useand, consequently, when subjected to abnormal increase in pressure byreason of expansion taking place when exposed to a rise in temperatureusually during the day time in the hot sunlight or for other reasonssaid pressure increases to an undesirable value, thus giving rise toleakage and fire hazard. Gasoline is usually cool and contracted whenfirst pumped up from an underground storage into a dispensing apparatusand thereafter expands greatly, exerting dangerous pressure, as itabsorbs the heat from the surrounding atmosphere above the ground.

It is a further object to provide pressure normalizing means, ingasoline dispensing apparatus, irrespective of the form of meter used,whether said meter is of the inside by-pass type, or of the so calledsolid type, whereby the pressure variations in the flow lines, exposedeither to heating or cooling conditions, are compensated for andmaintained within controlled pressure limits. This is attained in mycombination comprising,

Vw Lrnongnther things, a pressure relief means and a pressure storingand pressure feeding means. If the pressure in the line rises, thepressure relief means draws oi some gasoline, but if it falls the lineis supplied with gasoline; hence pressure compensating is attained. Ineither event, the gasoline passes through or around the meter withoutmovingmor. altering the position of theindi ""'catidial and recorderthereof. This invention, therefore, accommodates or makes use of anytype of meter, whether of the (first mentioned) by-pass valveaccuracy-adjustment type which will permit passage therethrough of alimited or gradual creeping flow due to gradual rise or fall of pressurein the ilow line, or of the second mentioned) mechanical-accuracyadjustment type which will resist this slow ow in either direction as anincident to variation of the internal pressure in the conduit ow system,due to the fact that the second mentioned meter is solid, so called,because it is sealed between its inlet and outlet and has no f,

acts as a positive pressure means to effect a feedl invention: f'

back of gasoline into the pipe to compensate for pressure decreasetherein.

'Ihe accompanying drawings show several forms of my invention,comprising metered dispensing apparatus in the form of curb pumps andthe like, by which to illustrate the principles involved, and inaccordance with'vhich various other forms of construction may beproduced without departing from the spirit of the invention.

Reference is first made to the views in the draw ings in respect to thetwo forms of meters above named by which to explain the pressurecompensating, equalizing, or normalizing operation, taking place in theapparatus, when not dispensing.

Figures 1, 2 and 4, 5 while showing two different forms of dispensingapparatus nevertheless employ the first mentioned meter ordinarily knownas the by-pass valve accuracy-adjustment type because this meter housingcontains an internal by-pass opening regulated in size by a needle valvewhich may be finelyadjusted manually to vary the size of said opening bywhich Jthe accuracy of the meter is periodically checked and correctedto dispense precisely the amount of liquid indicated on its dial. Thisform of meter readily permits the slight back and forth creeping flow inthe conduit system, without moving the meter mechanism. incident topressure variations and compensation therefor.

On the other hand, Figure 3, with Figure 2 as a part thereof, shows adispensing apparatus employing the second mentioned meter ordinarilyknown as the mechanical-accuracy adjustment type wherein any error iscorrected by resetting the meter mechanism such as varying the stroke ofthe piston in this well known type of meter. This form of meter offers aresistance to the slow creeping flow incident to variations in linepressure and compensation therefor because it does not contain theneedle-valve controlled by-pass opening. as first mentioned. I have,therefore, provided means, as in Figure 3, to accommodate my noveldispensing apparatus to this well known meter, by which the gradual ow,incident to lne pressure.varlation and compensation, may take place ineither direction, without going thru the meter.

A preliminaryy description of each view in the accompanying drawings andposition of parts will now be given in respect to all three forms of theFigure 1 shows a front view of a curb pump stand with the housingthereof broken away in vertical section to expose the inside parts. Theflexible service hose is hanging up on its hook and consequently themotor and suction force pump are not running and the ow line is full ofconfined gasoline. The direct-ion of the arrows, as applied to thisview, indicates that internal gasoline or vapcr pressure is building up,or in fact has already reached the needed pressure relief stage, in theconduit flow lines. 'I'his abnormal pressure is exerting and relievingitself reversely backv through the dispensing line, directly through therst mentioned meter and into a pressure relief absorption vacuum chamberwhich forms a feature of this invention in both forms thereof and whichconserves the excess gasoline and4 vapor and returns it to the flowlines to prevent waste.

Figure 2 shows an enlarged fragmentary portion of the pressurenormalizing or compensating means, but the apparatus is in a state ofdispensing operation, in that the motor and force pump are running. Thedirection of the arrows 8.'.

indicates that the pressure gasoline, previously accumulated out of thelines to reduce their pressure as in Figure 1, is being returned to theoutlet line and dispensed along with gasoline sucked up from a storagetank.

Figure 3 shows a side elevation of a modified form of the invention moreespecially provided forV the second meter heretofore discussed, namely,the mechanical-accuracy `adjustment type, or so called solid meter. Thisview il1ustrates the apparatus at rest, not in dispensing use, with thedischarge hose nozzle placed on its pivoted support hook. A meterby-pass or pressure equalizing line is open and leads the gradual flow,incident to contraction or expansion of the conlined gasoline, aroundthe solid meter so as to avoid applying a pressure on or thru it.Variation and equalization of the pressure in the lines is accomplishedaround and not thru this meter.

Figure 4 shows a modified form of the dispens- 1;.

ing apparatus, showing a flow indicator or visi gage which cf course maybe used with all forms of the invention. 'I'his view also shows thefirst mentioned meter. The pressure normalizer combination, includingthe pressure relief and pres- 11` sure supply chambers, is located inthe upper part of the pump stand. The direction arrows are applied, inthis view, to demonstrate a pressure storing and feed-back operation bywhich to compensate for a drop in the hydrostatic head 1j of theconfined gasoline column in the outlet or discharge pipe line and itshose taking place between dispensing operations.

Figure 5 is a detail section of the pressure compensating unit meansshown in Figure 4 and 1j comprising a pair of chambers, one of negativepressure for drawing ofi gasoline, and the other of positive pressurefor feeding back gasoline, to maintain the normal hydrostatic head inthe outlet line.

The invention is illustrated in connection with an upright pump ordispenser stand, ordinarily known as curb pumps, which are in use generally at gasoline filling stations, in garages and the like, and whichare usually installed at the streetY curb or on the sidewalk forconvenient service to motor vehicles, or at docksfor 'marine service.The pressure compensating apparatus shown inside the stand or stands isof course useful in other environments, particularly so on wall panelpumps where the meter and related apparatus is installed inside of abuilding and onveniently grouped cn a panel support attached to astanding structure such as a wall of the building. Also the apparatuscomprising my in- 1, vention may be used in connection with fuel pits Aninlet flow pipe line 8 connects with a stor- 1115 of supply 5, and thusa liquid column is confined 15 in the full length of the conduit flowline system\ of the dispensing apparatus, which includes the outletandflexible hose hereinafter named. Usually the check valve 9 is locatedsome distance from the pump stand 6 and either at or within the storagetank 5, but for convenience it is here shown at the bottom of the stand6. The upper end of the inlet pipe 8 may be connected with another checkvalve housing 10 usually tted with a spring seated valve head 1lnormally closing an inlet port 12.

In case this second check valve 10 is used in the inlet line 8, theupper end of its housing 10 communicates with the inlet side of asuction force pump vl5 ,which operates to vdraw gasoline up from storagetank 5 thru inlet pipe 8 and force it outwardly thru a discharge pipeline 13 connected to the other side of the pump. The check valve 10 alsoserves to maintain gasoline in the outlet line 13 and in the pump 15between dispensing operations. Any suitable form of suction and forcepump per se, such as the rotary pump 15 shown, may be included in theconduit flow line system 8, 13.

In the illustrated embodiment of the invention, there is shown a unitpipe-connection housing le to which the inlet pipe 8 and outlet pipe 13are rdirectly attached thereby placing these two pipes in communicationwith each other thru the force pump 15 but avoiding direct rattachmentof the piping system to the casing 15 of the pump itself. In the`housing 14 there may be provided the usual strainer' means and by-passvalve for the force pump 15, instead of mounting these parts within thepump casing 15, or otherwise providing therefor. The pump lcasing 15journals a driven pulley 16 affording a self contained pump which isstructurally independent of and removable from the pipe-connectionhousing 14. A base flange 1'? on the pump 15 secures the latter to thevertical face of the pipeconnection housing 14 by cap screws 18.

The pump 15, 16 is usually driven by an elecy tric motor 20 having apulley 21.,.oparrating the pump pulley 16 through a belt 2 2 or-othertransmission means. The motor 20 is supported in the pump stand 6 in anyconvenient manner, as for example on a horizontal cross bar support 23having its ends anchored to the vertical pump stand housing 6 or to aframe therein. Likewise, the pipe-connection housing 14, which entirelysupports the self contained pump 15, 16 may, to advantage. be xed to andentirely carried by any suitable inside frame or the cross support 23.The housing and pump assembly 14, 15 is rst installed in the dispenserstand 6 and thereafter it is a simple matter to install the pipingsystem without disturbing the pump 15. The conveniences and advantagesinherent inthis construction are more fully set forth in my Patent1,913,128 issued on June 6, 1933.

The discharge outlet pipe line 13 extends upwardly thru the pump stand 6and thru a meter 25 having the usual indicating dial 26. This me- ;er isof the by-pass valve accuracy-adjustment type, as hereinbeforediscussed. Said outlet pipe 13 projects from the top of the pump stand 6and ordinarily turns down for convenient connection with a flexibleservice discharge hose 27.

When not dispensing, this nozzle 28 is supported on a hose hook 29projecting from the pump stand 6. The hose hook 29 is usually a pivotedlever operatively connected with a motor starting switch, but thatfeature is not directly related to this first form of the invention andaccordingly is not yet shown in detail.

An\air cushion and pressure feed-back dome 31 is disposed upright withinthe dispensingstand 6 and constitutes the pressure storing element of ahydrostatic normalizing unit or compensator combination. This member 31is a positive pressure means and has its lower end connected directly toand in continuously open communication with the outlet pipe 13. For thispurpose, a pipe T or a cross-pipe tting 32 supports the bottom of theair dome 31 in open communication on the outlet pipe column 13. This airdome 31 ordinarily contains more or'less gasoline with entrapped air orgas vapor thereabove. The upper end of the chamber 31 is sealed andliquid surges upwardly into it, atthe end of a dispensing operation whenthe discharge nozzle 28 is suddenly closed, until the air or gas vaporentrapped'above the liquid level is compressed to a value wherel itresists further ingress or surge up of the liquid. It follows,therefore, that a pressure is stored or accumulated in the chamber 31 ata somewhat greater head than the outlet flow or pumping pressure in theline 13 when dispensing under the force of the pump l5. Note that thedotted line on the dome 31 in Figure l indicates a volume of gasolinetherein and shows the approximate level of the gasoline filling thelower end of said dome and that the vapor in its upper end iscompressed, the stored energy of which reacts to maintain full the Aflowlines and keep pressure thereon to offset for shrinkage ofthe connedliquid column.

The entrapped air or gas vapor, above the liq.- uid level in the chamber31, serves as 'a cushion or buffer against the inertia of a flowingliquid column when the latter suddenly stops and thus prevents undueshock and strain on the flow lines when the discharge hose nozzle 28 issuddenly closed at the ond of a dispensing operation. It is this shockabsorbing and cushioning function of the air dome 31 which energizes itwith stored up pressure of a somewhat higher degree or value v than theow pressure from the force pump 15, and which stored pressure acts asa'feed-back to the flow line 13 to return liquid thereto from dome 31 tocompensate for a drop of f pressure therein and thus maintain a solidv`and full column of liquid throughout the now lines and in a nowindicator when it is used. Also, the gasoline light ends or vaporsrising to the head of the dome 31 and compressed therein arecontinuously absorbed or condensed back into the liquid and no wasteoccurs thru evaporation.

From the foregoing, in reference to the air dome 31, it will now beunderstood, in my invention, that said dome constitutes a shockabsorbing cushion, a pressure accumulator, a pressure feed-back means,and a condensing means to reabsorb the gaseous vapors to conserve themotor fuel. With this one chamber 31, having in itself no moving parts,I accomplish these several functions, and consequently I employ the airdome in a new way and attain improved results and mode of operation,especially with other apparatus of my invention, as will now beexplained.

A description will now be given of the pressure relief element of thegeneral combinatie-n, the operation of which also saves all gasoline andvapor, returning same to the discharge line 13, 27 during eachdispensing operation, and minimizes the danger of leakage and reducesfire risk.

A negative pressure chamber 34 is disposed upright in the pump stand 6and constitutes the pressure relief vacuum absorption element in mypressure normalizer combination. It has its lower end connected thru adrain or return pipe 35 to the check valve housing 10 with the resultthat the lower end of the vacuum chamber 34 is always in opencommunication with the inlet ow line 8 and the inlet side of the forcepump 15, thru the valve 10 if it is used. When the pipe 35 is connectedto the inlet line 8 below the check valve head 11 and its port 12, thegasoline accumulated in the relief chamber 34 may drain back to the line8 to keep the latter full or even empty its contents back into thestorage tank 5. The upper end of the vacuum chamber 34 is connected by apipe 36, thru a pressure relief valve housing 37, and with the outletline 13 lat a point above the pump 15. Therelief valve 37 is showndiagrammatieally and any approved type may of course be used.

The pressure relief valve h0us1ng37 1s fitted with a valve head 38normally closed against its seat defining an inlet port in directcommunication with the outlet flow line 13. This valve head 38 iscarried on a stern 39 operating in a cage or other retainer in the usualway and having a manual adjustment to regulate it to a predeterminedsafety pop-off pressure. A spring 40 normally closes the valve 38, 39against its seat formed in the housing 37. The resistance of the spring40 is considerably greater than the flowpressure or head produced by theforce pump 15 in the discharge line 13. Consequently this spring 40easily maintains the pressure relief valve 3'? closed, as shown inFigure 2, during all dispensing operations, to positively shut olfcommunication between the dispensing line 13 and vacuum chamber 34,during that phase of operation. The pressure relief valve 37 has itsspring or variable means 40 adjusted to pop-off or automatically open,by yielding compression of said spring 40, at a hydrostatic head orpressure (when notl dispensing) at about 40 pounds in the severalcommonly-used gasoline meter pumps. Approximately a 35 to 45 poundadjustment for the safety relief Valve 37 is found to functionsatisfactor-ily by which the relief means 34 may take in or absorb anyexcess pipe and hose line gasoline pressure or vapors attaining anunsafe hydrostatic head substantially higher than the dispensingpressure and higher than the surged-up stored pressure in the air dome31 heretofore described. T'ne pop-o adjustment of the safety or reliefvalve 37 depends on a variety of factors, particularly the pumping orflow-pressure and safety requirements.

lt is noted that the pressure relief chamber 34 is connected into theflow line 8, 13 around the force pump unit 14, l5. This arrangementmeans that the vacuum chamber 34 by-passes the pump l5 due to the upperend of said chamber being connected into the conduit flow system 8, 13,27 above the pump and the lower end thereof connected'to the line belowthe pump. Hence all back or reverse flow of liquid or vapors, to relievethe pressure on the outlet line 13, 27 goes around the pump and back tothe inlet side 8 thereof. In this way, the excess pressure accumulatedgasoline, taken out of the discharge line 13, 27 to relieve its internalconfined pressure, is again wicked up by the pump 15 and returned to theline 13 during the next operation when the station attendant is sellinggasoline.

A dispensing operation (and the function and noveltgr of this invention)is better understood by :eference to Figure 2 where the arrows indicateactual dispensing flow. The gasoline is being drawn up from the storagetank 5 and is also belng sucked downwardly and out of the vacuum chamber34 into the inlet line 8. Upon starting the suction force pump 15, thecheck valves 9 and 10 open and the force pump 15 propels the gasolineoutwardly thru the meter 25 and discharge nozzle 28, during which thepressure relief valve spring 40 is positively holding its valve head 38closed on its seat against the dispensing flow so that no gasolineenters the pressure relief chamber 34. The level of gasoline conservedin the vacuum chamber 34 is rapidly dropping, as indicated by the arrowin the chamber, due to the dispensing operation. Since the pressurerelief valve 37 above the chamber 34 is closed (Figure 2) while theforce pump 15 is running, it follows that the drop of the liquid levelin chamber 34 sets up an atmosphere or gaseous rarefaetion thus producmge negative pressure or vacuum. This action conditions or energizes thechamber 34 for its next pressure relieving function when the dispenseris at rest and the hydrostatic pressure of the conned liquid column runsup in the hose and pipe lines to the safety limit of say 40 or 50 poundspressure at which the safety valve 37 is set to open.

Continuing the dispensing operation in the above paragraph, but turningnow to the air cushion and feed-back dome 31, the gasoline is propelledup thereinto until the vapor or air above the rising liquid levelequalizes with the pumping or flow-pressure and said level then comes torest. Hence the dome 31 is now surcharged with pressure equal to that ofthe dispensing pressure. The dome 3l does not necessarily contribute tothe dispensing operation, although priming itself by receiving liquid,as seen in Figure 2, whereupon the compressed vapor at pumping pressureabove the liquid level acts as a cushion to absorb the shock and inertiaof the flowing column of liquid when the discharge nozzle 28 suddenlycloses at the end of the dispensing operation being described.

This last named function produced a surgedup pressure in the dome 31higher than the pump dispensing pressure because the nal rush of liquid,propelled by inertia, surged upwardly into the dome 31 and compressedits light end vapors and air above pumping and dispensing pressure avery appreciable amount. This over-pump surged-up hydrostatic head inthe dome 3l was instantly trapped when the hose nozzle 28 and inletcheck vrgrlve 10 closed. This inertia-produced pressure in the dome 31now reacts or feeds back reversely to instantly impose a line pressuresome number of pounds above dispensing pressure. The result is atendency for steady back flow of gasoline from the dome 31 into the line13 to coni tinuously restore or compensate for any shrinkage of theconfined liquid column itherein. The presy sure relief Valve 37, it isto be remembered, is set at a pop-open pressure higher than the overpumpsurged-up pressure accumulated in the -1 therein.

lof the arrows which indicate back pressure in valve in the line 8.After a time, the expansion ofv this confined liquid rises to the safetylimit of the relief valve 37 and it automatically opens, as intherein.system does "not take in air but keeps itself filled dicateddiagrammatically in Figure 1, and the excess gas pressure then ows intothe chamber 34. The rise of pressure in the flow lines frequentlydevelops or starts in the service hose 27 dueto it ordinarily beingexposed to the sun and pushes back thru the lines. The vacuum previouslyinduced in the pressure reducing or absorption chamber 34, by reason ofthe former dispensing operation, facilitates removal of a quantity ofgasoline and vapor pressure from the outlet' flow line 13, 27 and aidsin popping open the automatic pressure relief valve 37 by which to drainsome of the gasoline from line 13 down in to chamber 34. The valve'- 37instantly closes as soon as enough liquid has drained from the line 13to relieve its excess pressure and lower same down to some predeterminedvalue, say about 40 pounds or to Whatever pressure the valve 37 may beadjusted, as required by safety regulations.

1t is noted by the dotted lines in Figure 1 that the receiving of excesspressure gasoline into vthe relief vacuum chamber 34 from the dischargeline 13 thru the open valve 37 is raising the level of the gasoline insaid chamber and hence is reducing the internal pressure on the conduitlines 8, 13 and 27. The dotted lines in the chamber 34 indicate that itis about half lled with excess pressure accumulated gasoline. On theother hand', it is noted in the dispensing view Figure 2 that thegasoline level in the vacuum chamber 34 is dropping, flowing out, andhas reached a very low level, due to the fact that the gasolinepreviously accumulated therein, incident to relieving the internalpressure on the hose line 27, is being drained off and returned to theoutlet line 13 by the pump 15. At the same time, the air is beingrarefied in the upper end of the suction chamber 34 thus re-energizingit for the next pressure relief operation on the pipe and hose lines 13,27.

Now as lto a pressure restoring operation, it has heretofore beenmentioned. However, reference is made to Figure 1, Where the reader mustnecessarily regard the relief valve 37 as closed instead of being opensince the pressure feedback chamber 31 only functions when the reliefvalve 37 has long since closed to cut-out the vacuum chamber 34 so thelatter cannot absorb the restorative pressure from dome 31. Contractionor shrinkage of the liquid. gasoline in the flow lines 8, 13 and 27comes about by evaporation thru the hose 27, leakage, a dropinitemperature and cooling of the apparatus at night'or seasonably, orby operation of other causes. Unless compensated for, the conduit systemwill begin to draw in air. The pressure feed-back vcierne `3l fullycorrects for this by gradually forcing its'" reserve of gasoline intothe line 13 in exactly the same proportion shrinkage occurs The resultis that the conduit flow solid with gasoline under the hydrostaticpressure or head of the vapor pressure formerly built up atthe end ofthe next prior dispensing operation when at the termination thereof theliquid surged up into the dome 31, as hereinabove explained. Theconstruction described herein, therefore, does not need or use an aireliminator because air cannot leak into the flow lines.

It is noted that in the generalarrangement of the apparatus within Vthecurb pump stand 6 that the meter 25 may be installed in the upperportion of the housing or pump stand while the liquid propelling orforcing means l5 and motor 20 are disposed in the lower portion of thestand. The air cushion feed-back dome 31 is placed between the meter andmotor driven pump. As to the vacuum chamber pressure relief means 34,its upper portion is connected to the outlet flow line 13 and its lowerend is connected to the pump 15 on its inlet side. While the first viewsportray this particular relation of parts, it is to be understood thatchanges in these positions may be made without departing from thepurpose and spirit of the invention, as observed for example in Figures4 and 5.

Thesecond form in FigureY 3 This form of the invention is especiallydevised for use in connection with a meter 43 of the second type havinga mechanical-accuracy adjustment means, (sometimes called a solid meter)as heretofore briefly discussed in the opening statements of thisinvention. Such a meter resists gradual slow iiow and does notsatisfactorily" from the flow line and normal pressure restoredv withoutin any way passing the gasoline through and disturbing the position ofthe meter dial and its piston mechanism.

Figure 3 of thedrawings shows the hose and its discharge nozzle hangingin non-dispensing po- I have, therefore, prosition on a pump stand 42. Ihave coordinated 4 this modified form of the invention with a motormeter 43. In this manner, the equalization of pressure in the connedliquid column in the conduit system 13, 27 is effected around the meterwith the latter cut-out of the ilow system. The upper part only of adispensing stand 42 is shown inasmuch as the same pressure absorptionchamber 34 and the related feed-back dome 31 in Figures 1 and 2 are usedin conjunction with this bypassing line and valve means.

The discharge or outlet flow line 13, heretofore described in Figures 1and 2, is also shown in Figure 3 as extending upwardly thru thedispensing stand 42. The line 13 is connected with the meter mechanismor bowl 43 of this mechanicalaccuracy type usually housing .the pistonor other driving means for actuating the recording and dialing means 44.The outlet pipe line 13 continues from the meter bowl 43 upwardlythrough the stand 42 and connects with the upper end of the service hose27 having the discharge nozzle 28, as heretofore described. Duringdispensing operations, the gasoline flows upwardly through pipe 13 andmeter 43, indicating the measurement thereof on dial 44, and outwardlythrough the hose 27 to an automobile or other point of consumption. Atthe end of the dispensing operation the nozzle 28 is placed on a pivotedhose hook support lever 45 fulcrumed at 46 on any suitable support, asfor example on a switch box 47 mounted inside the stand 42. This tiltinghose hook 45 is employed to stop and start the motor and pump means 20,15 later explained.

A by-pass pipe line or pressure equalizing tube 49 connects the outletpipe 13 around the meter 43, thereby shunting or cutting-out the latterand placing the two sections of outlet piping 13 in direct communicationwith each other, when not dispensing, instead of going thru the meter43, as when dispensing. A by-pass valve '50 is included in the by-passpipe 49 for positively closing this line when in dispensing u se. Avalve arm 51 is-xed on the movable element or core of the valve 50. Anoperating link 52 has its lower end pivotally connected to this valvearm 51 and its upper end pivotally connected at 53 to the rear end ofthe tiltable hose nozzle support 45; and this pivot 53 comprises aswitch actuating p'm, the rear end of which projects beyond thepivotally connected lever 45 and link 52 for a purpose to be described.

-The foregoing valve actuating link 52 and related parts are so arrangedthat when the leverlike hose hook 45 is down, due to the weight of thehose and discharge nozzle 27. 28 thereon as in Figure 3, the by-passValve 50 is automatically opened. This operation serves to directlycommunicate the flexible discharge hose 27 back to the lower section ofoutlet piping 13 behind or below the meter 43, which connection takesplace around said meter 43 now by-passed or cut-out from the entireconduit ow system 8, 13, 27. On the other hand, when the nozzle 28 isremoved for dispensing use and the operator is compelled to manuallythrust up the hose hook lever 45 to start the motor 20 in Figures 1 and2, the bypass valve 50 is then automatically closed through the downwardthrust of the link 52 which rotates the by-pass valve core 50 topositively close the by-pass \valve line 49, whereupon the meter 43 isagain cut-in so the upward iiow of gasoline, when dispensing, can onlytake place through the meter 43.

'I'he switch box 47, heretofore mentioned, contains any suitable form ofelectric switch 55 for opening and closing an electric power circuit 54to operate the pump-driving motor 20 in Figure l. A switch arm 56 isfixed to the switch 55 for actuating the latter. A forked lever 57 isfixed on a shaft 58 journalled in the switch box 47 and coacts with theswitch arm 56 to actuate the latter. The switch arm 56, with itsoperating means 57 and other mechanism therefor, are standard inconstruction and hence are diagrammatically shown. A switch mechanism ofany approved form is housed within the switch box 47. The shaft 58 isfixed in an operating yoke having two spaced parallel arms 59 swingablein a common plane transversely to the rear end of the projecting switchactuating pin 53 which also operatively connects the valve link 52 andhose hook 45.

The pivot and switch actuating pin 53, fixed in the rear end of the hosehook 45, piojects into the yoke 59 land lies within the operating planeof its two arms and consequently is engageable by rst one arm 59 andthen the other. This yoke has its two arms 59 spaced apart and thus thehose support lever 45 has some freedom of action or movement in relationto said yoke 59 and consequently to switch arm 56. Therefore, a greatertravel of the member 45 occurs for a shorter throw of the switch arm 56and this movement is adequate to actuate the by-pass valve 50. It isthis manually-operable mechanism which compels the operator to close theswitch 55 to start the motor 20 by an up movement of the outer end ofthe hose nozzle support lever 45 before he can dispense gasoline. Thereverse operation is, however, automatic because the weight of the hoseline 27, 28 opens the switch 55 when the hose is replaced on its support45. The link 52 is, therefore, coordinated with this switch operatingmechanism 45, 59 so it follows that the pressure equalizing by-pass lineand valve means 49, 50 is simultaneously set to perform its functionwith the manual starting and stopping of the motor and pumping means 20,15.

In the performance of a dispensing operation, the operator closes theswitch 55 and starts the motor 20, as above described. This operationsimultaneously and positively closes the by--pass line 49 by reason ofthe interconnections 51 and 52 between the by-pass valve 50 and switchoperatng mechanism 45, 59. Hence there is no possibility of dispensinggasoline through the bypass line 49 and around the meter withoutmeasur-ng it because said meter 43 is now positively and manually cut-inthe flow line 13, 27 when the motor 20 starts.

At the end of the dispensing operation, the station attendant replacesthe discharge hose on the lever support 4 5 and the weight of the hoseand nozzle throws the front end of said member '45 to its down cut-offposition. This opens the switch 55, thereby opening the power circuit 54to stop the motor 20 and pump 15, at the same i time pulling up on link52 to open the by-pass valve 50. The apparatus is now set to permit acompensating or pressure normalizing movelment which occurs thru acreeping ow of the liquid in either direction back and forth thru theconduit system from the closed discharge valve nozzle 28 to the checkvalve 10, by which excess gasoline pressure is either taken into thevacuum chamber 34 when internal expansion becomes excessive, or tolallow the over-pump hydrostatic pressure in the feed-back dome 3l tourge gasoline back into the line to keep it full and counteract',- ner adiminished pressure therein.

The/third form in Figures 4 and 5 This species of the invention isillustrated in connection with a visible flow indicator known as a visigage and also shows a simple grouping of the pressure normalizingchamber combination in the upper portion of a dispensing stand 61. Thesetwo views may also employ either form of meter, the rst mentioned formis shown, i. e., like the meter 25'in Figure 1 of the internal by-passvalve accuracy-adjustment type, and I designate it as in this thirddescription. l

The stand 61 receives an inlet pipe 62 having its lower end connectedwith a source of gasoline supply or a storage tank 63 and its upper endis connected with a pumping unit 64, 65 similar to the one previouslydescribed or of any approved suction force type and driven by a motor66. The inlet pipe line 62 is provided with a check-valve 67 of anysuitable form located at any' convenient point to retain the gasoline upin the pump and flow lines.

" relief chamber 81. spring 88 is tensioned or set to permit automaticner/8,59%

An outlet or discharge pipe 69 has its lower end connected to thepumping unit 64, and its upper end communicates with a standard meterbowl 70 having an indicating dial 71. The discharge or outlet gasolineline 69 extends thru the upper end of the dispensing stand 61 andcarries a depending flexible service hose 72 fitted with a dischargenozzle 73 placed on a hose hook support 74 projecting from said stand.

` It is usual to provide a -visible flow indicator 75 ordinarily knownas the visi gage. This indicator comprises a glass container 75 risingfrom a base 76. It is usual practice to connect the hose 72 anddischarge line 69 to this base 76, whereupon the gasoline rises upwardlyin the visi gage sight chamber 75. Usually apropeller 77 spins in theVisi gage glass so as to make it readily apparent that gasoline isflowing thru the sight chamber into the discharge line 69, 72 and henceto the customer.

Figui-esa and 5 show the air dome and pressurerelief chamber placed inthe upper yend of the dispensing stand 61 at a point adjacent theconnection of the pipe 69 with meter 70. By

` way of illustration, there is provided a pipe flt- `port .80 in thestand 61 may support the meter 70 and the tting 79 if desired to therebycarry the vacuum relief chamber 81 and air dome 82. l

'from collecting therein and thus avoids an in- However, in someinstallations, the pressure compensating unit 81, 82 is supporteddirectly by the upright pipe line 69 by use of a separate Tconnection-or other pipe tting for each chamber. Both chambers 81 and 82have their lower ends placed in communication with the line 69 and theirupper ends are sealed.

A pipe nipple or other fitting 84 may be used to support the air dome 82in upright service. position on the manifold 79. The pressure reliefvacuum chamber 81 may be screw-threaded down on to a neck 86 integralwith the pipe fitting or unit housing 79. A pressure relief valve 87,during all dispensing operations, is held nbrmally closed by a spring 88against a valve seat formed at the upper end of neck 86. Any form ofpressure .relief valve may be used and it opens into the vacuum chamber81 so that excess or abnormal pressure in the line 69, above pumpdispensing pressure and above the feed-back pressure from dome 81, mayforce open the relief Valve 87 to admit a quantity of gasoline upwardlyinto the The relief or safety valve opening of the valve 87 whenA thehydrostatic head in the flow line 69 reaches a safety limit ofpredetermined value and to which the relief valve 87 is adjusted. Inthis form of the invention,-1 preferably locate the vacuum chamber highup in the stand to minimize the tendency of the vacuum chamber to liftor draw liquid u tliereinto from the inlet pipe line 62.

The lower end of the pressure relief chamber 81 is connected thru a tubeor drain pipe 89 to the lower and hence inlet side of the pump unit 64,65. For this purpose, the pipe 89 may be connected at the lowerextremity of the hollow pipe-connection housing 64 on the vertical faceof which the motor driven pump 65 is carried.

` The suction of the pump 65, therefore, evacuates or draws the pressureaccumulated gasoline from the relief chamber 81 and returns it to theoutlet line from whence it came. It is preferable to include a checkvalve 90 in the tube line 89 so that the ow of liquid can take place inone direction only and that is downwardly from re lief chamber 81 totheinlet side of the pumping unit 64, 65.. This check valve 96 opensunder the suction flow downwardly to the pump in the direction of thearrows applied to the line 89 so that there is no possibility, when notdispensing, of liquid being sucked up into the vacuum chamber 8l fromthe lower portion of the piping system or from the inlet side of thepump 65.

At the end of a dispensing operation, the rush of liquid upwardly thruiiow line 69 is suddenly stopped when the discharge nozzle 73 is closed,whereupon the inertia of the fast moving liquid column surges upwardlyinto air dome 82 with the result that the air or gas vapors in said domeabove the liquid level is compressed and surged up to a degree abovethat of normal dispensing or pumping pressure, but below the popoifpressure of the safety relief valve 87. This inertia-produced pressureis conserved in the upper end of the air dome 82 and acts to feedgasoline therefrom back into the discharge lines 69 and 72 should thereoccur contraction of the confined liquid column, as by a drop intemperature, due to evaporation, or for other causes. In this way, thedome 82 feeds back gasoline under pressure to the flow lines to keepthem normally full and thus exclude air from the lines. The pressurerestoring dome 81 maintains the visi gage 75 full and prevents air orgas bubbles elcient and erroneously measured liquid dispensingoperation.

The air cushion and pressure restoring chamber 82 is preferably placedhigh up-in the dispensing stand 61 to avoid too great a difference ingravity head between the visi gage 75 and said chamber. By locating thechamber or dome 82 comparatively close .to the visi gage, it followsthat most of the inertia-produced vapor pressure, in the upper end ofsaid dome above the liquid therein, is actually available for impressingthe gasoline from said dome out thru the meter 70 and up the pipe line69' into the visi gage' and down the hose line 72. It is noted that thereference HC denotes the initial and maximum height of the liquidsuddenly forced up into the 'or cont'r ti'on of the liquidin the linecaused by a drep in temperature. The arrows in the dome Sportray theexpansive force of the high compression HC level working the entrappedliquid downwardlyt'o/'effect pressure compensation throughout the flowlines.

It may also be pointed out that" the correct operation of the air dome82 is not dependent on the surged-up over-pump pressure. It is obviousthat the termination of a dispensing operation will leave a storedpressure in the dome 821 at least equal in value to that of pumping-flowpressure and this is true even though the operator very slowly closesthe discharge nozzle 73 kso that the liquid may not be surged up intothe dome and produce the high compression HC. Furthermore the .storedpressure in the dome 82 may gradually drop below that of pumping pressoIsure. In any event, the stored pressure is suiiicient to always keep theflow lines full because the compressed vapor in the dome is elastic andexpands to push back in the flow line at all times.

The pressure relief chamber 81 absorbs or draws off pressure from theline"69, 72 and thereby compensates for an abnormal increase or overpressure which might tend to produce leaks and cause damage and loss ofmotor fuel. In this connection, it is to be remembered that the pressurerelief valve 87 is set to automatically open and admit gasoline into thechamber 81 at a higher pressure than the pressure generated in the airdome 82 when the discharge nozzle 73 was suddenly closed. Hence the airdome 82 can always perform its function of feeding pressure gasolineback into the line 69, 72 without losing its effect due to misoperationof the relief valve 87 nasm/uch as said valve cannot open in response tothe comparatively lower feed-back pressure acting from said dome. Alsothe stored pressure in dome 82, will rell or restore the liquid columnin the lines after excess pressure therein has opened the relief valve87 and the vacuum chamber 8l has drawn off considerable liquid, followedby a shrinkage of the liquid column due to a long period ofnon-dispensing.

This invention lls a need felt for a safe, ecient gasoline dispensingapparatus, wherein the liquid lines are always Well lled and maintainedat substantially normal pressure.

What is claimed is:

1. A curb pump comprising an upright dispenser stand enclosing a flowline, including a meter and suction force pump, and a discharge hoseconnected with the flow line and carried on the stand; a pressure reliefchamber closed to atmosphere, a relief valve interconnected between thechamber and the flow line and adjusted to positively close against thedispensing force of the pump, and an open ilow connection from thechamber to the suction side of the pump whereby said pump evacuates saidchamber.

2. A liquid dispenser comprising a flow line including a discharge hose,a meter in the fiow line, a suction force pump to dispense liquid thruthe meter and flow line, means to reduce the hydrostatic pressure of theconfined liquid in the flow line when not dispensing, including anegative pressure means, a relief valve connecting the negative pressuremeans to the flow line, said relief valve remaining closed against thedispensing pressure of the pump but adapted to open when the hydrostaticpressure in the flow line rises to a predetermined value, and a drainconnection between the suction side of the pump and the negativepressure means to evacuate the latter and induce a negative pressuretherein during dispensing operations.

3. A liquid dispenser comprising an outlet line having a meter therein,an inlet line having a check valve and adapted to connect with a sourceof liquid supply, a suction force pump interconnected between the outletand inlet lines, a discharge hose and nozzle connected with the outletline and closed to confine liquid in the lines from the nozzle to thecheck valve, a chamber by-pass -connected around the pump with theoutlet line between the pump and meter and to the inlet line to take inliquid from the outlet line and return it to the inlet line, and anormally closed valve means between the chamber and the'outlet linewhich opens upon excessive pressures existing gin the latter.

4. A liquid dispenser comprising an outlet line having a meter therein,an inlet line having a check valve and adapted to connect with a sourceof liquid supply, a suction force pump interconnected between the outletand inlet lines, a discharge hose and nozzle connected with the outletline and closed to confine liquid in the lines from the nozzle to thecheck valve, a pressure relief chamber, a relief valve interconnectedbetween the chamber and outlet line, said relief valve adapted topositively hold. closed against the' force pump on its outlet sideduring dispensing operations but adapted to open under a greaterpressure to admit liquid into the chamber and reduce the pressure in thelines, and a continuously open communication between the chamber and theinlet suction side of the pump to evacuate said chamber when the pump isrunning.

5. A curb pump comprising an upright dispensing stand enclosing a flowline, a meter in the-upper portion of the stand through which the flowline conveys and measures the dispensed liquid, a flexible hoseconnected with the upper end of the flow line and having a dischargenozzle closed and hanging on the outside of the stand when not indispensing use, a suction force pump and a driving motor thereformounted in the lower portion of the stand and lsaid pump being connectedwith the ow line to force liquid therethrough, an upright air domemounted in the stand above the suction force pump and the lower end ofsaid dome being connected in continuously open communication with theflow line at a point above said pump; and a pressure relief chambermounted upright in the stand and connected with the flow line thru apressure relief valve which positively closes against the ow linepressure of the pump when dispensing but adjusted to open under a higherpressure when not dispensing, and a ow connection between the reliefchamber and the inlet side of the force pump whereby the suction of saidpump evacuates said relief chamber.

6. A dispensing stand enclosing a ow system, a discharge hose carried bythe stand and connected with the flow system, a meter and a suctionforce pump supported by the stand and communicating with the flow systemto measure and propel liquid therethrough, and a pair of chambersforming means to normalize and maintain substantially a constantpressure in the flow system when not dispensing; one chamber being apositive pressure means and having its lower end in continuously opencommunication with the flow system above the pump, to absorb the inertiashock of the suddenly stopped column of liquid in the flow system at theend of a dispensing operation, thereby energizing itself with afeed-back pressure higher than the pump -propelling pressure tocompensate for shrinkage of the conned liquid column in the flow systemwhen not dispensing; the other chamber being a negative pressure meanshaving an outflow connection with the inlet side of the suction forcepump by which the latter evacuates said negative pressure means into theflow system to remove liquid therefrom and induce a negative pressuretherein, and a pressure relief valve between the negative pressure meansand flow system and adapted to open at a pressure higher than thefeed-back pressure of the positive pressure means and higher than thepump propelling pressure by which to suck in liquid from the flow systemin event of excess pressure therein.

7. A liquid dispenser comprising a flow line including a meter and aliquid forcing means to propel the liquid through the line fordispensing operations, a pressure relief chamber, means to communicatethe chamber with the flow line only when the hydrostatic pressure hasreached a predetermined value in said flow line above dispensingpressure, and an air cushion dome in continuously open communicationwith the ow line to receive the shock of the suddenly stopped liquid owat the end of a dispensing operation thereby building up a hydrostatichead greater than the dispensing pressure but lower than the aforesaidpressure of predeterminedvalue.

8. A gasoline dispenser comprising a flow line including a meter and adischarge hose, propelling means to force gasoline through the flow lineand produce a suction to draw it into said line, a pressure reducingchamber in constant communication with the suction of the fiow line bywhich gasoline drains from the chamber to said flow line and a negativepressure is induced in said chamber,- a pressure relief valveinterconnected.

between the pressure reducing chamber and the flow line and said valvebeing set to positively close against the propelling pressure throughthe flow line and against the negative pressure in the pressure'reducing chamber, said pressure relief valve being set to open underexcessive hydrostatic pressure of the flow line to draw gasolinetherefrom into the pressure reducing chamber, and an air dome inconstant communication with the flow line between the discharge hose andpropellingmeans and adapted to receive gasoline surged up thereinto as aresult of the inertia of the suddenly stopped dispensing flow whichcompresses the air therein and adapts said dome to maintain the flowline under pressure when not dispensing.

9. A liquid dispenser comprising a flow line including a meterand'liquid propelling means, pressure normalizing means to maintain' thehydrostatic head in the flow line at substantially a constant pressureand approximately at dispensing pressure, including pressure reliefmeans connected to the flow line to reduce the line pressure, pressurerestoring means connected to the ow line to retain dispensing pressurein the ow line in order to increase the line pressure and compensate fordiminished pressure when not dispensing, 'and means to positively shutoil communication between the iiow line and pressure relief means at thepressure delivered by the liquid propelling means.

l0. A liquid dispenser comprising a flow line including a meter andliquid propelling means, pressure normalizing means to maintain thehydrostatic head in the ow line at substantially a constant pressurewhen not dispensing; including a vacuum chamber connected to the flowline, a pressure relief valve between the vacuum chamber and flow line,said relief valve being adjusted to remain closed against the pressureof the liquid propelling means, but to open under a hydrostaticpressure, when not dispensing, of substantially greater value than theflow pressure of the liquid propelling means; and an air dome in opencommunication with the ilow line, to cushion the shock of the suddenlystopped liquid flow, store up air pressure of higher value than the ilowpressure but less than the hydrostatic pressure at which the reliefvalve opens, and thus keeping the ilow line (when not dispensing) undera normal pressure higher than the liquid propelling pressure but belowthe pressure at which the relief valve opens.

11. A liquid dispenser comprising a ow line and discharge hose,including a'liquid forcing means to propel liquid through the line fordispensing operations, a pressure relief chamber, means to communicatethe chamber with the ilow line only when the hydrostatic pressure hasreached a. predetermined value in said now line above dispensingpressure; and a pressure storing chamber having its lower end incontinuously open communication with the flow line with entrapped air atits upper end, to receive the shock of the suddenly stopped liquid flowat the end of a dispensing operation, thereby compressing the entrappedair to greater pressure than the dispensing pressure but lower than theaforesaid pressure of predetermined value, whereby the compressed airacts to feed back liquid into the flow line tokeep the latter underpressure when not dispensing.

12. A curb pump comprising an upright dispensing stand enclosing aconduit ow line, a meter in the stand through which the flow line'conveys and measures the dispensed liquid, a

hose connected with the upper end of the flow line and having a.discharge nozzle hanging on the outside of the stand when not indispensing use, a`4 suction force pump and driving motor thereformounted in the lower portion of the stand and said pump being connectedwith the ow line to force liquid therethrough, an upright air domemounted in the stand and the lower end of said dome being connected incontinuously open communication with the flow line at a point above theforce pump; and a pressure relief chamber mounted upright in the standand connected with the flow line above the force pump thru a pressurerelief valve which is positively closed against the flow line pressureproduced by said pump when dispensing but adjusted to openI underabnormally high pressure, and a flow connection between the reliefchamber and the inlet side of the force pump whereby the suction of saidpump evacuatesv said relief chamber, the air dome and pressure reliefchamber serving to maintain a normal and safe pressure when notdispensing by equalizing directly thru the meter by reason of a gradualand slow liquid movement in either direction thru said meter.

13. A liquid dispenser comprising an out1et line having a hose anddischarge nozzle closed when not dispensing, a meteri'n the outlet line,a suction pump connected with the outlet line, an inlet line connectedwith the force pump and adapted to communicate with a source of liquidsupply, a check valve in the inlet line to trap and hold liquid in bothlines from said check valve to the closed discharge nozzle; a pair ofchambers connected in the lines, one chamber being positive pressurecharged by the pump pressure and the inertia of the owing liquid whenthe discharge nozzle is closed at the end of a dispensing operation, theother chamber having communication with the suction side of the pump andbeing negative pressure energized and-also communicating thru a reliefvalve with the outlet line; whereby the gradual. movement ineitherdirection of liquid directly thru the meter when not dispensingdue to pressure variations in the lines, is equalized by the positiveorl liO mounted above the outlet flow line and connected therewith, adischarge hose carried by the stand and connected with the outlet flowline and with the visible ilow gage, a meter and a suction force pumpsupported by the stand and included in outlet flow line to measure andpropel liquid thru the flow gage and hose, a nozzle on the hose adaptedto be closed to keep the line full when not dispensing, a pair ofchambers forming means to normalize and maintain substantially aconstant pressure in the line when not dispensing; one chamber beingpositive pressure charged and having its lower end in continuouslyopencommunication with the ow system above the pump, to absorb theinertia shock of the suddenly stopped column of liquid in the flowsystem at the end of a dispensing operation, thereby energizing itselfwith a feed-back pressure somewhat higher than the pump propellingpressure during the dispensing operation, and by which to compensate forany shrinkage of the confined liquid column in the line and keep itunder pressure to maintain a full charge of liquid in the visible flowgage when not dispensing; the other chamber being energized by anegative pressure and having an outow connection with the suction sideof the pump by which the latter evacuates said chamber, and a pressurerelief valve between the negative pressure chamber and the line andbeing set to open at a positive pressure higher than the feed-back ofthe positive pressure means by which to drawoff a quantity of liquidfrom the hose, the visible flow gage, l

and the line, in event expansion therein produces an abnormal pressure.

l5. A liquid dispenser comprising a flow line including a meter and asuction pump, a visi gage and a hose connected to the flow line,pressure -normalizing means to maintain the hydrostatic head in the lineat substantially a constant pressure when not dispensing to keep theline and visi gage full, including a vacuum chamber connected to theiiow line, apressure relief valve between the vacuum chamber and flowline, said relief valve being adjusted to remain closed against thepressure of the suction pump when dispensing, but to open under ahydrostatic pressure of greater value than the pump pressure when saidpump is not running so as to relieve excess pressure in the hose andvisi gage as well as the line, and an air dome in open communicationwith the flow line to cushion the shock f the suddenly stopped liquidflow and store up air pressure higher than the ow pressure but lowerthan the hydrostatic pressure at which the relief valve opens to keepthe ow line under pressure when not dispensing and consequently preventa drop of the liquid level in the visi gage.

16. A curb pump comprising a dispensing stand, an outlet flow lineextending from the top of the stand, a hose and discharge nozzle carriedon the stand and connected with the outlet line, a visi gage to indicateflow thru the hose, a meter in the outlet line, a pump having its outletside connected with the outlet line, an inlet line convvnected with theinlet side of the pump and adapted to communicate with a liquid supply,a check valve in the inlet linel to retain the inlet and outlet linesfull of liquid from said check-valve to' the discharge nozzle, an airpressure dome gmounted in the upper part of the stand and having itslower end connected with the outlet .line to entrapair and compress itabove the liquid therein at the end of a dispensing operatQIl and henceurge liquid back into the line to keep the visi gage filled, and avacuum chamber connected with the outlet line thru a relief valve totake in excess pressure generated by expansion in the lines, and an openconnection between the vacuum chamber and inlet line to evacuate saidchamber.

17. A gasoline dispenser comprising an upright pump stand enclosing asuction force pump, a meter, an outlet and an inlet line; a hose anddischarge nozzle carried on the stand, and a visi gage on the stand toindicate flow thru the meter to the hose; a pressure reducing chambermounted in the vupper end of the stand and in open communication withthe suction side of the pump by which gasoline flows from the chamber tosaid pump and a negative pressure is built up in said chamber, apressure relief valve interconnected between the pressure reducingchamber and the outlet line and said valve being adapted to positivelyclose against pumping pressure in the outlet line and against thenegative pressure in said chamber, said pressure relief valve being setto open under excessive hydrostatic pressure of the outlet line to drawliquid therefrom into the reducing chamber, and an air dome mounted inthe upper end of the stand and in constant communication with the outletline between the visi gage and pump and adapted to receive gasoline upthereinto as a result of the inertia of the suddenly stopped dispensing'flow which compresses the air therein and produces a pressure adapted tofeed back gasoline into the outlet line and visi gage under pressure toavoid intake of air should shrinkage occur in the confined liquid.

18. A liquid dispenser comprising a ow line including a meter and liquidpropelling means, a hose and nozzle connected therewith, a visi gage toindicate flow, pressure normalizing means disposed adjacent the meterand proximate the visi gage to maintain the hydrostatic head in the flowline at substantially a constant pressure when not dispensing and tomaintain the visi gage full, including pressure relief means connectedto the ow line to reduce the line pressure, pressure storing andfeed-back means connected to the flow line at an upper position thereinto increase the line pressure, and means to positively shut oicommunication between the flow line and pressure relief means at theoperating pressure o f the liquid propelling means.

19. A liquid dispenser comprising an outlet line having a visi gage andhose, a meter in the outlet line, a pump to dispense liquidtherethrough, a pair of closely mounted upright chambers having theirlower ends disposed proximate the meter and connected with the outletline adjacent the meter, one chamber being in open communication withthe outlet line and adapted to entrap liquid and compressed air thereinand feed back said liquid under pressure to keep the outlet line andvisi gage full between dispensing operations, a pressure relief valve inthe connection for the other chamber to the outlet line and positivelyclosed against the dispensing pressure but opening under higherpressures to discharge liquid from the outlet line, and a drainconnection from the last named chamber to the pump by which the liquidis returned to the outlet line.

20. A liquid dispenser comprising an outlet line supported on the pipefitting and opening directly thereinto and adapted to receive liquidfrom the hollow member andA retain a charge of compressed air in itsupper end at the termination of each dispensing operation and to feedback into the outlet line to keep full the visi gage as 4well as thehose when not dispensing, av pressure 21. A curb pump comprising anupright dispensing stand enclosing a meter, an outlet line running thrusaid meter, a pump connected with the outlet line, a hose and dischargenozzle connected with the outlet line and carried on the stand, a hosesupport pivoted on the 4stand on which rests said hose and nozzle andthe weight of which actuates said support, a by-pass valve and pressureequalizing line connected into the outlet line around the meter, and anoperating connection between the by-pass valve and the pivoted hosesupport so that said valve is actuated by the weight of the hose andnozzle as aforesaid, whereby the dispensing ow is directed thru themeter but the liquid movement seeking equalization ,in pressure takesplace thru the by-pass valve and pressure equalizing line. y

22. A curb pump comprising an upright dispensing stand enclosing ameter, an outlet line running thru said meter, a pump connection withthe outlet line, a hose and discharge nozzle connected with the outletline and carried on the stand', a hose support pivoted on the stand onwhich rests said hose and nozzle and the weight of which actuates saidsupport, a by-pass valve and pressure equallzing line connected into theoutlet line around the meter, and an operating connection between theby-pass valve and the pivoted hose supportfso that said valve isactuated by the weight of the hose and nozzle as aforesaid, and pressurenormalizing means .in communication with the outlet line below theby-pass valve and pressure equalizing line, whereby the dispensingy owis thru the meter but the liquid movement incident to normalizing thepressure is thru the by-pass valve and pressure equalizing line.-

23. A liquid dispenser comprising a pump and outlet line having a meter,a hose and nozzle connected with the outlet line, a visi gage toindicate ilow, a by-pass pressure equalization line and valve connectedaround the meter to the outlet line, a pivoted hose support on whichrests the hose and nozzle to actuate said support, an operatingconnection between the pivoted hose support and by-pass valveautomatically opening the latter when the hose hangsat rest on itssupport, and

pressure compensating means in the outlet linel 'joutlet line having ameter, a hose and nozzle connected with the o`utlet line, a visi gage toindicate flow, a by-pass pressurel equalization line and valve'connected'around the meter to the outlet line, a pivoted hose supporton which rests the hose and nozzle to actuate said support, an opierating connection between the pivoted hose support and by-pass valveautomatically opening the latter when the hose hangs at rest on itssupport, an electric switch, an operating connection between the switchand pivoted hose support whereby the switch is open when the by-passvalve is open, and pressure compensating means in the outlet line belowthe by-pass valve and pressure equalizingline comprising a negativepressure means to draw liquid out of the outlet'line and positivepressure means to feed liquid to the line to maintain it and the visigage full despite contraction of the liquid therein.

25. A liquid dispenser comprising a discharge line and hose, a meter, asuction pump on the inlet side of the meter to dispense liquidtherethrough, a by-pass valve for the meter which closes to direct thedispensing ow thru the meter but opens to afford a free movement ofliquid in the discharge lnefwitho'ut passing thru said meter when notdispensing, a vacuum chamber having a drain connection with the suctionside of the pump, and a pressure relief valve communieating the vacuumchamber with the discharge line and adapted to open under pressureconsiderably greater than the dispensing pressure to remove excessliquid from the line.

26. A liquid Adispenser comprising a discharge line and hose, a lmeter,a suction pump on the inlet side of the meter to dispense liquidtherethrough, a bi1-pass valve for the meter which closes to direct thedispensing flow thru the meter but opens to afford a free movement ofliquid in the discharge line in both directions without passing thrusaid meter when not dispensing, a visi gage in the discharge line toindicate flow, a pressure storing means for the discharge linecomprising an air chamber, continuously open at its bottom to thedischarge line betwen'the pump and the by-pass valve, said air chamberentrapping air and liquid in its upper portion at the end of eachdispensing operation, and adapted to' feed liquid into the dischargeline and thru the open by-pass valve when not dispensing to compensatefor a drop'in pressure in said line and maintain the visi gage full.

27. A liquid dispenser comprising a discharge line and hose, a meter, asuction pump on the inlet side of the meter to dispense liquidtherethrough, ahy-pass valve for the meter which closes to direct thedispensing flow thru the meter but opens to afford a free movement ofliquid in the discharge line in both directions Without passing thrusaid meter when not dispensing, a vacuum chamber having a drainconnection with the suction side of the pump, a pressure relief valvecommunicating the vacuum chamber with the discharge line and adapted toopen under pressure considerably greater than the dispensing pressure toremove excess liquid from the line, a visi gage in the discharge line toindicate ow, a pressure storing means for the discharge line comprisingan air chamber continuously open at its bottom to the discharge linebetween the pump and the by-pass valve, said air chamber entrapping airand liquid in its upper portion at the end of each dispensing operation,and adapted to feed liquid into the discharge line and thru the openbypassvalve when not dispensing to compensate for a drop in pressure insaid line and maintain the visi gage full.

28. A liquid dispenser comprising a flow system and discharge linehaving a hose and nozzle normally closed to retain liquid in said linewhen not dispensing, a-visible flow indicator in the discharge line, ameter included in the discharge line, a pump adapted to draw liquid froma source of supply and dispense it thruthe meter and discharge line `asshown by the flow indicator, a pressure equalizing line having one endconnected with the discharge line between the hose and meter and itsother end connected to said line-between the pump and meter therebybypassing said meter, a by-pass valve in the pressure equalizing line, amanual control for the by-pass valve to close said valve when dispensingand open it to cut out the meter and permit flow in both directions whennot dispensing, and means communicating with the flow system tocompensate for a pressure variation in the hydrostatic head of the.conned liquid, said pressure variation and the means to compensatethereof acting thru the open by-pass valve and pressureA equalizing linewhen not dispensing and with the meter cut-out of the discharge lineline, a pump under the meter to propel liquid thru the line; an air domelocated above the pump under the meter and having its lower'end openinginto the line to receive liquid into the lower end of said dome andcompress air inl its upper portion at the end of a dispensing operationand act as a pressure feed-back chamber for the line to compensate for adrop in pressure therein, an upright vacuum chamber under the air domeand adjacent the pump and having a drain connection to the inlet side ofthe pump, and a relief valve connection between the upper portion o'fthe vacuum chamber and the outlet line and adapted to open underpressure considerably greater than dispensing pressure to drain excessliquid pressure from the line into the chamber. I

30. A liquid dispenser comprising a stand enclosing a meter; an outletline running through said meter including a hose, a discharge nozzlecarried on the hose, and a normally closed'valve meansbetween the meterand nozzle; a hose supporting means movably mounted on the stand onwhich said hose and nozzle is hung. when not in use and the weight ofwhich actuates said supporting means, a pressure equalizing lineincluding a by-pass valve connected into the outlet line around themeter, an operating connection between the oy-pass valve and the movablehose supporting means so that said by-pass valve is actuated to openposition by the weight of the hose and nozzle as aforesaid, whereby the.dispensing flow is directed through the meter but .the liquid movementseeking equalizationv in pressure when not dispensing liquid takes placethrough the by-pass valve and pressure equalizing line, and a pumpconnected with the outlet line.

31. A curb pump having a meter to measure the ow of liquid comprising adispensingy stand, an outlet line in which the meter is connected, adispensing valve means in said outlet line controlling the dispensingofliquid therethrough, a pump connected with the outlet line, an inletline connected with the pump and adapted to be connected with a sourceof liquid supply, a pump by-pass connection connecting the inletand/outlet lines and operable to circulate the liquid therethrough uponclosing of the dispensing valve, a check valve in said inlet linepreventing return flow of liquid to the liquid supply, a negativepressure chamber connected to the inlet line on the liquid supply sideof said check valve, and a relief valve connecting the outlet line withthe negative pressure chamber and relieving pressures in excess ofdelivery pressure. v

32. A curb pump having a meter to measure the ow of liquid comprising adispensing stand, an outlet linein which the meter is connected, adispensing valve means in said outlet line controlling the dispensing ofliquid therethrough, a pump connected with the outlet line, an inletline connected with the pump and adapted to be connected with a. sourceof liquid supply, a pump by-pass connection connecting the inlet andoutthe liquid supply side of said check valve, a relief chamber incontinuous open communication with the outlet line.

WILLIAM J. PETER.

